Computer file system

Abstract

A computer file system, in which directory files and real files are organized in a tree structure, includes data items which are recorded in a high-ranking directory file in the tree structure, a high-ranking file management table which records file management data indicative of the assignment relation with low-ranking directory files or real files created below the high-ranking directory file, and a low-ranking file management data which is stored in any of the low-ranking directory files and indicative of the assignment relation between the low-ranking directory file and other low-ranking directory files or real files. The system further includes an assignment relation copy device which copies the file management data of a high-ranking or low-ranking file management table indicative of the assignment relation between the high-ranking or low-ranking directory files or real files into another high-ranking or low-ranking file management table.

I claim: 
     
       1. A computer file system in which directory files and real files are organized in a tree structure comprising: a recording medium for storing the directory files and the real files;   first and second high-order file management tables stored in respective high-order directory files which occupy high-order positions in the tree structure;   low-order directory files and real files occupying positions below the high-order directory files in the tree structure, said first and second high-order file management tables each storing file management data indicative of a storage assignment between data items written in a high-order directory file and at least one of the low-order directory files and real files occupying positions below the high-order directory files;   first and second low-order file management tables stored in respective low-order directory files for storing file management data indicative of a storing assignment between data items written in the low-order directory file in which said first or second low-order file management table is stored and at least one of the real files and the low-order directory files other than the low-order directory file in which said first or second low-order file management table is stored;   input means for designating first file management data in at least one of said first high-order file management table and said first low-order file management table and for designating second file management data in at least one of said second high-order file management table and said second low-order file management table;   a copy source file management table for storing said second file management data designated by said input means;   a copy destination file management table for storing said first file management data designated by said input means;   edit means for editing said file management data of at least one of said first high-order file management table and said first low-order file management table in said copy destination file management table by copying said second file management data from said copy source file management table into said copy destination file management table; and   write means for writing the first file management data edited by said edit means in a memory area in said recording medium at the position at which said file management data was stored prior to editing in one of said high-order management table and low order management table.   
     
     
       2. A computer file system according to claim 1, wherein, if neither a directory file name nor a real file name in one of said second high-order file management table and second low-order file management table as specified by said input means in said second file management data exists in the one of said first high-order, file management table or said low-order file management table, said assignment relation copy means copies file management data of one of said second high-order and second low-order file management table into file management data of one of said first high-order file management table and said first low-order file management table. 
     
     
       3. A computer file system according to claim 1, wherein said edit means includes assignment relation copy means which, before and after copying of file management data of one of said first high-order and first low-order file management tables, records an indication of a relation between a high-order directory file and a low-order directory file, into a parameter recording area in said system. 
     
     
       4. A computer file system according to claim 3, wherein said assignment relation copy means records, into a pertinent data item of a file management table of one of said first high-order and first low-order file management tables which is stored in said copy destination file management table, information that the pertinent data item has been edited. 
     
     
       5. A computer file system according to claim 1, wherein said assignment relation copy means copies file management data indicative of a storage assignment relation between one of said first high-order file management table, said first low-order file management table, and said real files into a file management table of one of a newly created high-order file management table and a newly created low-order file management table written under control of said assignment relation copy means in said recording medium. 
     
     
       6. A computer file system according to claim 5, wherein said assignment relation copy means creates said newly created directory file in a position in said tree structure below at least one of a second high-order directory file and a second low-order directory file. 
     
     
       7. A computer file system according to claim 5, wherein said assignment relation copy means records a storage relation corresponding to one of a directory name and a real file name which expresses a position in said tree structure of one of a directory file and a real file identified by said directory name and real file name, respectively, before and after copying of file management data of said directory file and a real file as a directory connection of a high-order file management table in a parameter area in said system, and records an indication that file management data has been copied in a file management table of one of a directory file and a real file. 
     
     
       8. A computer file system according to claim 1, further comprising assignment relation copy means for controlling the copying of second file management data from said copy source file management table into said copy destination file management table. 
     
     
       9. A computer file system according to claim 8, wherein said edit means includes assignment relation copy means, and said assignment relation copy means reads file management data in a second high-order or low-order file management table of one of said high-order directory and said low-order directory, respectively, into said copy source file management table, reads file management data in a first high-order or low-order file management table of one of said high-order directory and low-order directory, respectively, into a copy destination file management table, edits file management data read into said copy source file management table which is added to file management data of said copy destination file management table, and writes an edited file management table from said copy destination file management table into one of said first high-order directory and said first low-order directory. 
     
     
       10. A computer file system according to claim 9, wherein said assignment relation copy means copies all of file management data in a file management table of one of said first high-order and first low-order file management table into said copy destination file management table and edits the copied file management data with file management data of one of said second high-order file management table and second low-order file management table residing in said copy source file management table. 
     
     
       11. A computer file system according to claim 8, wherein said assignment relation copy means copies file management data in a first high-order or low-order file management table of one of said high-order and low-order directory files into a file management table of a newly created directory file written under control of said assignment relation copy means in said recording medium. 
     
     
       12. A computer file system according to claim 11, wherein said assignment relation copy means creates said newly created directory file in a position in said tree structure below one of a second high-order directory file and a second low-order directory file. 
     
     
       13. A computer file system according to claim 11, wherein said assignment relation copy means records a storage relation corresponding to one of a directory name and a real file name which expresses a position in said tree structure of a one of a directory file and a real file identified by said directory name and real file name, respectively, before and after copying of file management data of said directory file and a real file as a directory connection of a high-order file management table in a parameter area in said system, and records an indication that file management data has been copied in a file management table of one of a directory file and a real file.